Liquid injection device



-B Q I QGS 4' H. BRINGER I 3,402,552

LIQUID INJECTION DEVICE Filed Nov. 5, 1964 United States Patent Office3,402,552 Patented Sept. 24, 1968 3,402,552 LIQUID INJECTION DEVICEHeinz Bringer, Vernon, France, assignor to Etat Francais (French State)represented by the Minister of Armed Forces, Ministerial Delegation forArmament, Direction of Researches and Manufacture of Armament,Laboratory of Ballistic and Aerodynamic Researches, Vernon, France FiledNov. 5, 1964, Ser. No. 409,251 Claims priority, application France, Jan.29, 1964, 961,921 1 Claim. (Cl. 60--39.74)

The present invention is concerned with a liquid injection device,notably for liquid-fuel rocket-type power units utilizing a combustionagent and a fuel, characterized in that it comprises a combustionchamber with injection orifices opening into this chamber in the lateralwall thereof, said injection orifices being grouped by pairs andinclined with respect to the lateral surface of the combustion chamber,with the axes of the two orifices of any pair converging to a pointwhere two jets of the same liquid propellants, whether oxidizer or fuel,are thus caused to meet as they are delivered from said two convergentorifices, so as to atomize these liquids at the point of convergence ofthese two jets, and that the points of convergence of the axes of thepairs of orifices causing the atomization on the one hand of said fueland on the other hand of said oxidizer alternate along the wall of thecombustion chamber in order to homogenize completely the two atomizedpropellants.

The liquid injection device according to this invention is capable ofproducing a uniform and efiicient atomization throughout the chamber,thus ensuring an optimum efiiciency.

Various forms of embodiment of this invention will now be described byway of example with reference to the accompanying drawing, in which:

FIGURE 1 is a longitudinal section showing a liquid injection deviceconstructed according to the teachings of this invention;

FIGURE 2 is a longitudinal section showing an alternate form ofembodiment of this device;

FIGURE 3 is a fragmentary developed view showing another form ofembodiment of this device.

The liquid injection device illustrated in FIGURE 1, designed for aliquid-fuel rocket-type power unit utilizing as propellants an oxidizerand a fuel, comprises a combustion chamber 1 formed inside asubstantially cylindrical member or casing 2 closed by a slightly domedor bulged bottom wall 3. This bottom wall 3 is covered by a cap 4bearing on an annular shoulder 2a formed on the outer periphery of saidcasing 2. In the center of this cap 3 a port is formed and has fittedtherein the outlet end of a feed pipe 5 supplying one of thepropellants, whether oxidizer or fuel, to the device.

The cylindrical casing 2 has longitudinal ducts 6 formed in its wall;these ducts 6 open into the space formed between the dorned bottom wall3 and the cap 4; they are disposed at regular spaced intervals about thelongitudinal axis of the device.

Each longitudinal duct 6 communicates through a pair of injectionorifices 7, 8 with the combustion chamber 1. As shown in FIGURE 1, theseinjection orifices 7, 8 converge towards each other and their axes meetat a point A. These orifices lead into a groove 11 of substantiallytrapezoidal cross-sectional contour, formed in the inner wall 2b of thecylindrical casing 2.

Similarly, the second propellant is atomized in the combustion chamber 1by means of other pairs of convergent orifices 12, 13 of which the axesmeet at a point B, as shown in the right-hand portion of FIGURE 1. Thepairs of injection orifices 12, 13 are also regularly spaced about thelongitudinal axis of the combustion chamber 1, and these pairs oforifices alternate with the aforesaid pairs of injection orifices 7, 8injecting the first ergol so that the points of intersection orconvergence A and B of the two propellants alternate in a sametransverse row in the order A,B,A,B,A,

The various pairs of orifices 12, 13 maybe connected in various mannersto a feed pipe supplying the second propellant. Thus, in FIGURE 1 eachpair of orifices 12, 13 open into a longitudinal blind duct 14 open atthe bottom and receiving this second propellant which has cooled thecombustion chamber beforehand.

Referring now to the second form of embodiment illustrated in FIGURE 2,wherein the injection device comprises three rows of pairs of injectionorifices 7, 8 on the one hand, and 12, 13 on the other hand, the threepairs of injecting orifices 7 and 8, 7a and 8a, and 7b and 8b injectingthe first propellant have their axes disposed in a same common meridianplane, these six orifices opening, as in the case illustrated in FIGURE1, into a common longitudinal duct 6 connected to the space formedbetween the domed bottom 3 and the cap 4. On the other hand, the secondpropellant is fed in this case according to a different procedure. Infact, it will be seen that the three pairs of orifices 12 and 13, 12aand 13a, 12b and 13b are connected to separate ducts 15, 16, 17 and 18leading into an annular chamber 19 connected to a feed pipe 21 supplyingthis second propellant. In this case too the first liquid propellant isatomized at the points of intersection A of the axes of thecorresponding injection orifices 7 and 8, 7a and 8a, and 7b and 8b, thesecond liquid propellant being atomized at points B where the axes ofthe jets issuing from orifices 12 and 13, 12a and 13a, and 12b and 13bare caused to converge.

According to a modified form of embodiment of this invention, the pairsof injection orifices 12 and 13, 12a and 13a, and 12b and 13b deliveringthe second propellant to the combustion chamber may open directly into acommon cavity formed in the outer surface of the cylindrical casing 2,these various cavities communicating in turn with the external annularchamber 19 connected to the feed pipe 21 delivering the second liquidpropellant.

The number of pairs of injection orifices such as 7 and 8, 12 and 13 ina same row, and the number of these rows are subordinate, of course, tothe desired output and atomization for each liquid propellant.

According to another alternate form of embodiment, all the pairs oforifices of a same row may be used for injecting a same propellant; inother words, this row comprises a succession A, A, A, A, of atomizingpoints, the pairs of orifices of the adjacent row injecting the otherpropellant; otherwise stated, this adjacent row provides the successionof points B, B, B, B, In this case, the atomizing points B may belocated in the same meridian plane at points A, or the atomizing pointsB may be disposed in a plane intermediate two adjacent meridian planescontaining the atomizing points A.

In a modified form of embodiment illustrated in FIG- URE 3 the injectiondevice comprises three rows of pairs of injection orifices 7, 8providing an atomizing point A for one of the propellants and of pairsof injection orifices 12 and 13 providing an atomizing point B for theother propellant. The pairs of orifices 7, 8 of these three rowscommunicate with helical ducts 22 and the pairs of orifices 12, 13 openinto similar helical ducts 23. These helical ducts 22, 23 alternate inthe cylindrical casing 2, as shown in FIGURE 3; they are connected tothe relevant feed pipes supplying the two liquid propellants. Thearrangement illustrated in FIGURE 3 is such that in each row theatomizing points alternate: A, B, A, B, and on the other hand thisalternation A, B is also obtained in the axial or longitudinaldirection. In this case each atomizing point A orB is surrounded by fouratomizing points of the opposite type, i.e., B or A, and thus theatomized liquid propellants are homogenized in a particularly efiicientmanner.

Of course, various modifications and variations may be brought to theforms of embodiment of the invention shown and described herein by Wayof example, Without departing from the spirit and scope of the inventionas set forth in the appended claim.

What I claim is:

1. Liquid injection device, notably for liquid rockettype power unitsutilizing an oxidizer and a fuel, which comprises fuel and oxidizersupply means, a combustion chamber having a longitudinal axis, acylindrical lateral wall and a domed bottom wall defining saidcombustion chamber, injection orifices formed through said cylindricallateral Wall and opening into said combustion chamber, said injectionorifices being grouped by pairs regularly spaced about the longitudinalaxis and inclined with respect to the surface of the combustion chamber,each pair of injection orifices communicating with either the fuelsupply means or the oxidizer supply means only, the axes of the twoinjection orifices of any pair being located in the same meridian planeand converging to an atomizing point where the two jets of the sameliquid propellant, whether oxidizer or fuel, issuing from said twoconvergent orifices, are caused to meet, whereby producing theatomization of said liquid at the point of convergence of the ReferencesCited UNITED STATES PATENTS 2,397,834 4/1946 Bowman 6()--39.74 2,523,6569/1950 Goddard. 2,555,080 4/1951 Goddard 6039.74 2,602,290 7/1952Goddard 6039.74 2,763,987 9/1956 Kretschmer 6035.6 3,242,668 3/1966Ellis 6039.74

OTHER REFERENCES Sutton, F. P.: Rocket Propulsion Elements, secondedition, Wiley & Sons, Inc., New York, 1956, pages 207, 208 relied on.

MARTIN P. SCHWADRON, Primary Examiner.

D. HART, Assistant Examiner.

1. LIQUID INJECTION DEVICE, NOTATABLY FOR LIQUID ROCKETTYPE POWER UNITSUTILIZING AN OXIDIZER AND A FUEL, WHICH COMPRISES FUEL AND OXIDIZERSUPPLY MEANS, A COMBUSTION CHAMBER HAVING A LONGITUDINAL AXIS, ACYLINDRICAL LATERAL WALL AND A DOMED BOTTOM WALL DEFINING SAIDCOMBUSTION CHAMBER, INJECTION ORIFICES FORMED THROUGH SAID CYLINDRICALLATERAL WALL AND OPENING INTO SAID COMBUSTION CHAMBER, SAID INJECTIONORIFICES BEING GROUPED BY PAIRS REGULARLY SPACED ABOUT THE LONGITUDINALAXIS AND INCLINED WITH RESPECT TO THE SURFACE OF THE COMBUSTION CHAMBER,EACH PAIR OF INJECTION ORIFICES COMMUNICATING WITH EITHER THE FUELSUPPLY MEANS OR THE OXIDIZER SUPPLY MEANS ONLY, THE AXES OF THE TWOINJECTION ORIFICES OF ANY PAIR BEING LOCATED IN THE SAME MERIDIAN PLANEAND COVERGING TO AN ATOMIZING POINT WHERE THE TWO JETS OF THE SAMELIQUID PROPELLANT, WHETHER OXIDIZER OR FUEL, ISSUING FROM SAID TWOCONVERGENT ORIFICES, ARE CAUSED TO MEET, WHEREBY PRODUCING THEATOMIZATION OF SAID LIQUID AT THE POINT OF CONVERGENCE OF THE TWO JETS,THE POINTS OF INTERSECTION OF THE AXES OF THE PAIRS OF ORIFICES WHICHEFFECT THE ATOMIZATION ON THE ONE HAND OF THE LIQUID FUEL AND ON THEOTHER HAND OF THE LIQUID OXIDIZER ALTERNATING IN A SAME PLANE TRANSVERSETO THE LONGITUDINAL AXIS OF SAID COMBUSTION CHAMBER IN ORDER PROPERLY TOHOMOGENIZE THE THUS ATOMIZED TWO LIQUID PROPELLANTS, AND SAID ATOMIZINGPOINTS OF ONE PROPELLANT ALTERNATE WITH THE ATOMIZING POINTS OF THEOTHER PROPELLANT IN THE LONGITUDINAL DIRECTION.